Sash balance



June 16, 1959 M. H. GREGG ETAL 2,890,480

sAsx-I BALANCE Filed April 5, 195e QAMHMW AttonNsY United States Patent C SASH BALANCE Mahlon H. Gregg, Rochester, and Frederick J. Decker,

Pittsford, N.Y., assignors to The Caldwell Manufacturing Company, Monroe County, N.Y., a corporation of New York Application April 5, 1956, Serial No. 576,372

6 Claims. (Cl. 16197) This invention relates to a window sash balance, and it more particularly pertainsto means provided for increasing or decreasing the tension of the spring member in a helix balance, or any other such balance wherein the longitudinal movement of a spiral rod through a nut is used with respect to the raising and lowering of a window sash.

In previous arrangements of this character, the winding and unwinding of the spring as the sash is raised or lowered is produced by moving a spiral or helical actuating rod between followers at one end of the cylinder. One end of the coil spring is fastened to the cylinder so as to be rotated, and the other end to be held stationary. However, with varying weights and sizes of sashes, the sash balance of this type must be provided with an adjustment means for the coil spring whereby suitable means may be used to make these adjustments according to need, without disengaging the entire sash balance from its operative position with respect to the window frame and sash.

An object of the present invention is to provide an improved and relatively inexpensive means for adjusting the torsional force of the spring of the sash balance of this character, so that the spring may have its torsional force readily changed while the balance is operatively connected to a window sash.

Another object of this present invention is to provide an adjustment means for the torsional force of the spring by turning a lower driver located therein. The turning of this lower driver, in turn, transmits the motion to the actuating rod, which turns the nut attached to the torque tube, which in turn, increases or decreases the tension of the spring member aixed thereto.

It is another feature of this present invention to provide a simple means for botto-m adjustment, allowing the sash balance to be used with various weights and sizes of window sashes, adapted to the needs of the simple adjustment means provided.

Another advantage of this invention is the fact that a simple tool like a screw driver, or other such similar tool, is used in connection with the adjustment means for adjusting the spring member in a sash balance of this character, while the sash balance remains in an operative position with respect to the window frame and the sash.

Other objects and advantages may be obtained and better understood after the following discussion of the detailed drawings.

Reference is made to the fact that this invention pertains to a means of adjustment for any type of balance wherein the principle of mechanical action is obtained with the use of a helical spring, using extension and torsion, or torsion alone, together with a nut and spiral actuating rod, where the necessity for adjustment to meet varying sash weights is required.

In accordance with the present invention, a locking pin is located in the lower anchor attached by suitable means to a window sash, is encircled by a spring member and is received in a slot in the lower driver located within the lower anchor. The lower driver, having a compression spring located between the upper driver, has an an nular groove. The upper drive is attached to a spiral actuating rod extending upward into a sash balance casing. The spiral actuating rod carries a nut attached to the casing or tube having the spring member axed there t0.

By inserting a screw driver, or other such similar tool, into the notch located on the bottom of the lower driver, and forcing the lower driver upward, the locking pin is disengaged from its original position in the slot; and re ceived in an annular groove, thereby allowing the lower driver to be free to turn. It is to be noted, that the force exerted by the screw driver on the lower driver, compresses the spring located therein, which in normal position separates the upper and lower drivers when the adjusting screw driver is withdrawn and allows the locking pin to return to a locking position in the slot. The lower and upper drivers are both circular sections of registering against each other and overlapped to avoid disengagement and provide turning elort to be directly transmitted from the lower driver, when rotated, to the upper driver. In turn, the spiral actuating rod is also rotated, being attached to the upper driver. As a result, the spiral actuating rod rotates a nut attached to the tube which carries the spring member. In this way, the motion of the lower driver, is transmitted to the upper driver having a spiral actuating rod attached thereto, which in turn rotates a nut attached to the tube carrying a spring member, thus increasing or decreasing the tension of said spring member. In this manner, the torsional force of the spring may be adjusted according to need without disengaging the entire sash balance from its operative position with respect to the window frame and the sash.

In the drawing:

Figure 1 is an enlarged cross section, in part, illustrating the means for adjusting the tensionof a spring used with a sash balance of this type.

Figure 2 is a cross section of the sash balance illustrating the operative position of the sash balance and adjusting means with respect to a window frame and window sash.

Figure 3 is an enlarged view, in part, of the slot and groove located in the lower driver arrangement which is somewhat like a one-tooth dog clutch, and a 180 circular section.

With reference now being made to the drawing, and in particular to Figure 2, a portion of the window sash, which is indicated by the reference character 11, is attached to an arm bracket '70, which is part of the sash balance designated as a whole by the reference character 15, by suitable means such as screws 16. An upper end 17 of the sash balance 15 is attached to the sash frame 19 by a screw 40, or other such suitable means. The upper portion 17 of the sash balance 15 has indents 49 formed therein which support a washer 65 carrying a non-friction bearing 63 which is allowed to revolve with the tube 1 having anged edges Z extending outwardly, thus holding the tube 1 in position with respect to the sash balance 15. A spring carrier 25 is aixed to the tube 1 and car ries a helical spring 23 mounted thereon which is coaxial with the spring carrier 25. A nut 30 rides on a spiral actuating rod 21 and is located within and attached to onev end of the tube 1, so that the motion of the spiral actuating rod 21 is transmitted by means of the nut 30 through the tube 1 to the spring 23. The spiral actuating rod 21 is attached and held stationary at its looped end 3 vto an upper driver 4, so that it enters and extends upwardly into tube 1.

The upper driver 4, holding the looped end 3 of the spiral actuating rod 21, extends, in part, into, and isp/held A in position by the inwardly bent ares 5 of the tube portion formed from .the lower .anchor 27. A spring 6 sep- I arates Athe upper driver 4 from the lower Ydriver A7. The upper driver 4 and the lowerdriver 7 are used as a register clutch, each having 180 of `circular sections with inner diameters -to house the .compression spring .6. may be clearly s een in Figure 3. |The lower driver 7 fhas a notch 8 located at .its bottom edge, and a slot 9 'located on .ione iside of the lower driver 7. The lower driver 7 also has .an annular groove 9A Vconnecting to the slot 9; said sl'ot 9 is adapted t9 receive a locking pin 10 entering the lower anchor 27 and engaging in the slot 9 when the mechanism is at rest. It will be noted vthat the compression spring V6 separates the upper driver 4 from the lower driver 7 when the adjusting tool is withdrawn, and allows the locking pin 10 to return to a locking position in the slot .9. This locking pin 10 when located in slot 9, is further aided with respect to retaining its position by means of the spring 23, which is coaxially aixed to the lower anchor 27.

lThe supporting arm bracket 70 has a drawn circularslotted section as represented in the drawing by the reference character 72, in which the embossed lug 71 of the lower anchor 27 registers to hold fast the lower anchor 27 aga-inst rotation. Thus, the spring 23 which is coaxially mounted on the lower anchor 27, and the spring carrier 25, is held fast, and the -force wound in the spring 2S is likewise held stationary, unless the spiral actuating rod -21 -is turned to revolve Vthe tube 1 to reduce or increase the sustained force to be delivered by the spring 23. The -anged lower edge 73 of the lower anchor 27, together with the drawn portion 18 of the arm bracket 70, take the weight of the sash 11, whereas, the inward ared portions of the lower anchor 27 retain the upper driver 4 from ejection.

Operation Assuming that the sash balance 15 is installed in position with respect to the sash frame 19 and the sash 11, the following is performed when more tension is desired in the spring 23.

,'Ihe -window sash 1,1 is raised so that a screw driver, or other such suitable tool may be inserted in the notch 8, :ai: :the same time forcing the lower driver 7 upward. With this action, as illustrated in the drawing, the locking pijn 1 0 is disengaged from the slot 9 and received in the annular groove 9A. As a result, the lower driver 7 iS unlocked from its original position with respect tothe lower anchor 27. Thus, the lower driver 7 is free to be turned as desired by means .of the `screw driver inserted in the notch 8. The force exerted on the lower driver 7 by the `screw driver, compresses the spring 6 located in the chamber formed by the upper driver 4 and the lower driver 7, allowing the engagement of the lower driver 7 to the upper driver 4, acting somewhat like a one-tooth dog clutch, so that when the lower driver 7 is turned, the spiral actuating rod 21, aixed to the upper driver 4, is also turned. The turning motion of the spiral actuating rod 21 lis transmitted to the nut 30. The nut 30, attached to the tube 1, turns the tube 1 and the spring carrier 25 having 'the spring 23 attached thereto, Thus, the turning of the lower driver 7 directly transmitted to the upper driver 4, in turn, rotates the spiral actuating rod 21. The spiral actuating rod 21 transmits this motion to the nut 30 attached to the tube 1, and turns the tube 1 carrying the spring carrier 25 having the spring 23 attached thereon. In this manner, the tension of the spring Z3 is increased according to the number of 4turns of the lower driver `7, according to need and in relationship with the sine and weight of the window sash 11.

When the desired increase in tension is obtained, the screw 'driver or other such similar tool used, is removed from the notch 8 of the lower driver 7. With this action, the locking pin re-enters the slot 9 when the lower driver 7 is allowed to drop down into its original position. The compression spring 6, housed within the lower driver 4 7 and the upper driver 4 aids in returning the locking pin 10 into Ya locked `position -in the slot 9. As a result, the lower driver 7 is held securely locked in position with respect to the lower anchor 27 by means of the locking pin 10 received in the slot 9 and the increased torsional force of the spring 23 is held fast.

A decrease in torsional force 4of the spring 23 is obtained by turning the -lower driver 7 in the opposite direction, that is, counterclockwise, thus unwinding the spring 23, as 'hereinabove mentioned and explained, and decreasing its ltorsional force.

'While specific embodiments `have been shown and described, it will, of course, be understood that various modications may yet be devised by those skilled in the art which will embody the principles of the present invention and found in the true spirit and scope thereof.

We claim:

1. A sash balance having adjusting means for adjusting the torsional force of a spring member in said sash balance mounted in a window frame, said adjusting means comprising a lower anchor attached by suitable means .to a window sash, a lower driver located therein and having an annular groove and a slot, an upper driver extending, in part, outwardly from said lower anchor and connected to a spiral Aactuating rod received in a rotatable tube, a spring separating said drivers in the locked position, a locking pin cooperating with said lower anchor `and adapted to be received in said slot and said annular groove, a spring member used to exert torsional force with respect to said sash balance for raising and lowering said window sash, said spring member being disposed coaxially with and attached to a spring carrier attached ,to said rotatable tube, said lower driver having a notch formed therein and located on the bottom .end .of the lower driver, an Vadjusting tool adapted to be received in said notch for turning said lower driver in order to transmit the turning motion to said spring, thus increasing or decreasing the torsional force of said spring member.

2. A sash balance having adjusting means for adjusting the torsional force of a spring member in said sash bala-nce mounted in a window frame, said adjusting means comprising a lower anchor held securely in position in said sash balance by suitable means and attached to a window sash by means of an arm bracket, a lower driver located within said lower anchor and having -a notch formed therein and located on the bottom of the lower driver adapted to receive an adjusting tool used to Vturn said lower driver, said lower driver having an annular groove and a slot formed therein, the slot being located in the lower driver above said annular groove and connected thereto, an upper driver, extending, in part, outwardly from said lower anchor, a spring separating said drivers in the locked position, said upper and lower drivers being semi-circular sections and acting like a one-tooth dog clutch and means for turning a spiral actuating rod connected to said upper driver, said spiral actuating rod received in a rotatable tube and means yfor rotating a nut attached to said tube, a spring carrier attached to said rotatable tube and carrying one end of said spring member attached thereto, said spring member being disposed coaxially with and attached to said spring carrier and said lower anchor, -a locking pin cooperating with said ilower anchor and adapted to be received in said slot when said lower driver is in a locked position and adapted to be received in said annular groove when said lower driver is free to turn, and above said Iadjusting means, in combination, means for increasing or decreasing the torsional force exerted 'by said spring member in said sash balance.

3. A sash balance having adjusting means 'for adjusting the torsional force of a spring member Vin said' sash balance mounted in a window frame, comprising an arm bracket attached to a window sash by suitable means, saidarm bracket having a drawn portion overlapping a hanged edge of a lower anchor, said arm bracket having a drawn circular section, slotted, to receive a lug formed :from said lower anchor, means for holding fast said lower anchor against rotation, a lower driver located said lower anchor and having a notch located on the bot-tom thereof, an adjusting tool adapted to be received in said notch and used to turn said lower driver when forced upward by means of the pressure exerted by said adjusting tool, an upper driver, extending, -in part, out- Wardly from said lower anchor and held from ejection by means of the inwardly flares formed from said lower anchor, said lower driver and said upper driver both circular sections, acting like a one-tooth dog clutch, registering against each other and overlapped to avoid disengagement and provide turning effort to be directly transmitted from said lower driver tto said upper driver having attached thereto a spiral actuating rod, a locking pin cooperating with said lower anchor and adapted to be received in a slot and an annular groove, formed in said lower driver, said locking piu received Iin said annular groove when said lower driver is forced upward, by means of said adjusting 4tool inserted in said notch, thus freeing said lower driver and allowing said lower driver to be yturned at the same ,time turning said spiral rod, which, -in turn, through a nut connected to a rotatable `tube carrying a spring carrier, winds or unwinds a spring member attached to said spring carrier, resulting in an increase or decrease in torsional lforce of said spring member, said locking pin received in said slot, connecting to said annular groove, when the desired tension is obtained by turning said lower driver, and said lower driver is allowed to return to its normal position, locked, when the adjusting tool is removed from said notch, the locked position of said lower driver with respect to said locking pin also aided by a compression spring being disposed said lower and upper drivers and separat ing said drivers, and said locking pin, when received in said slot, retaining said lower driver in a locked position, thus maintaining the adjusted torsional yforce exerted by said spring member of said sash balance.

4. A sash balance including a helical spring and a spiral actuating rod for applying torsional force to said spring, and means for varying the amount of force applied to the said helical spring by the said actuating rod, said means comprising; a lower anchor attached to a window sash, a lower driver located in sa-id lower anchor, an

upper driver located above said lower driver in said lower anchor, said upper driver being connected to said spiral actuating rod, said lower driver having an annular groove and a slot formed therein, a locking pin cooperating with said lower anchor and adapted to be received in said slot and said annular groove in said lower driver, said -lower driver having a notch formed therein, said notch being adapted to receive an adjusting tool for turning said lower driver in order to transmit the turning motion to said spiral rod, whereby to vary the amount of torsional -force applied to said helical spring.

5. In a sash balance having a helical spring and a spiral actuating rod for applying torsional force to said spring; adjusting means for varying the amount of force applied `to the helical spring by the spiral rod comprising, a lower anchor attached Ito a window sash by means of a bracket, an upper driver located in said lower anchor, said upper driver being attached to the spiral rod in the sash balance, a lower driver located in said lower anchor below said upper driver, said lower driver having a slot and an annular groove formed therein, a locking pin in said lower anchor adapted to be received in sa-id slot and said annular groove in said lower driver, said lower driver having a notch formed therein adapted to receive an adjusting tool for turning said lower driver, said upper driver being adapted to be turned by said lower driver, whereby to vary the amount of force applied to the helical spring in the sash balance.

6. Adjusting means -for varying the amount of force applied lto the helical spring in a sash balance wherein the force is applied to the helical spring by a spiral actuating rod, said adjusting means comprising an anchor fastened to said sash balance and connected to a Window sash, an upper driver and a lower driver in said anchor, said upper driver being fastened to the spiral actuating rod in the sash balance, said lower driver being turned by an adjusting tool, said upper driver being turned by said lower driver, whereby to vary the amount of force applied to the helical spring by the spiral actuating rod.

References Cited in the le of this patent UNITED STATES PATENTS 1,926,951 Larson Sept. l2, 1933 2,371,366 Viehweger Mar. 13, 1945 2,415,614 Tappan Feb. 1l, 1947 

